Ultrathin Photovoltaic Donor-Acceptor Structure with Opposite Built-in Fields

Abstract

We discuss organic heterostructures, in which ultrathin layers of an organic material alternate with layers of other organic materials, such as dyes, organic semiconductors or ferroelectric polymers. The study is focused on the distribution of an external electric field and the measurements of the built-in-fields in the donor and acceptor layers within photovoltaic heterostructures. The built-in-fields play an extremely im-portant role in development of organic solar cells, photodetectors, LEDs, transistors, etc. Our investiga-tions are based on the electroabsorption (or Stark spectroscopy) technique. As an example, built-in fields were studied on an organic solar cell heterostructure ITO-CuPc-С60-Al. Two strong built-in fields of oppo-site directions have unexpectedly been found in the bulk of the donor (copper phthalocyanine, CuPc) and acceptor (fullerene, C60) layers under equilibrium conditions. Such a phenomenon has not been observed earlier and owes to the particular accumulation of excess holes trapped at the CuPc / С60 interface. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/35359